The arrest of an 11-year-old Washington boy who brought a gun and more than 400 rounds of ammunition to school is the latest in a series of alarming incidents involving children and guns.

It was the latest incident involving a boy and a gun, but experts and statistics indicate that the number of shootings involving children has been declining in recent years.

The Washington boy was stopped Wednesday after he was discovered with the guns, bullets as well as knives at Frontier Middle School, according to the Associated Press. No one was hurt and school resumed.

The unidentified minor was expelled from school and arrested on suspicion of attempted murder. Court documents showed that probable cause was found only for attempted assault, unlawful possession of a firearm and possession of a weapon at school, the AP reported.

The boy said he heard voices in his head telling him to shoot another boy that he thought was bullying his friend, court documents said.

Earlier this week, a seventh grade student in Nevada used a semi-automatic gun to kill a teacher and injure two students before taking his own life. Investigators believe the 12-year-old obtained the Ruger 9mm semi-automatic handgun from his home, but authorities are still trying to confirm the origin of the firearm.

Despite recent reports of kids and guns, statistics on the issue have been improving.

Data from the Centers for Disease Control and Prevention shows that firearm deaths and death rates in children from ages one to 14 have declined from 1999-2010, the latest year the CDC has documented. There were 481 deaths involving kids and guns in 1999 and 369 in 2010.

Firearm homicides, firearm suicides and unintentional firearm deaths all decreased in that decade.

David Hemenway, a professor of health policy at Harvard's School of Public Health, said that the rash of recent incidents are not an indicator of a suddenly growing problem.

"I believe in the CDC numbers," Hemenway told ABCNews.com. "What is in the news is not a good epidemiology."

Hemenway said that children and guns have been a problem for a long time, and while the number of deaths have decreased, the decline should not underscore how "incredibly serious" the problem is.

"This sort of gets people's attention so now let's look at this issue and try to have more sensible policies and change social norms in ways that reduce the problems," he said. "We do know that areas in the United States where there are fewer guns and stronger laws, there are fewer gun problems."